Re: Laser Beams From Space

ICESat's orbit was changed Saturday 10/4 and is now in a 91 day
repeating ground track orbit.  Assuming the repeating ground tracks get
evenly spaced around the earth over the 91 days they should be spaced
approximately 14 miles apart at 40 degrees north.  So with some patience
ICESat should come close to you.

I have observed the laser three times now and for good viewing suggest
getting as close to the ground track as possible, hope for some thin
clouds, and look directly towards zenith.

When skys were clear observers have reported seeing only a brief green
flash at zenith but when there is some cloudiness to scatter the beam
the pass is much more interesting.

A photograph of a recent pass scattering through clouds is posted at

 http://www.gsfc.nasa.gov/topstory/2003/0920icesatfirst.html  

Gregg Hendry





Patty Winter wrote:
> 

> 
> Thanks for the heads-up on this, Greg. I ran out my local ICEsat passes
> on Heavens-Above, and although I'm getting two per night for the
> foreseeable future, they're all way east or west of me. ;-( Guess I'll
> keep checking and hope that some of them get higher in my sky.
> 
> Patty